Moore’s law is a law that essentially says that computing power has grown rapidly and will continue to grow rapidly. Specifically, it states that the number of transistors that can be put on one computer chip has doubled every 18 months or so in the past and that rate of growth will continue into the future. The practical meaning of this is that computers are getting faster and faster as time goes by.
If this is true, it means that password complexity needs to grow just as rapidly as computing power grows. To the average human being, it seems impossible to crack passwords through simple guessing. Passwords can be strings of random numbers and letters that no one could ever guess. But if computers are getting stronger and stronger in a very rapid fashion, they will be more and more able to guess passwords. What this means is that we need to keep making our passwords stronger and harder to guess. We have to keep making them more complex so that they will be too complex for computers to guess in a practical amount of time.
Moore’s law tells us that computers will get faster and faster. Therefore, we need to make our passwords stronger and stronger to keep up.